Ppp4r3a,也称为Smek1,是蛋白磷酸酶4(PP4)的调节亚基,在多种生物学过程中发挥重要作用。PP4是一种广泛存在于真核细胞中的丝氨酸/苏氨酸蛋白磷酸酶,参与细胞周期的调控、信号转导、DNA损伤修复和细胞凋亡等多种生物学过程。Smek1与PP4的催化亚基PP4c结合,形成PP4全酶,共同参与这些生物学过程的调控。
Smek1在多种疾病中发挥重要作用,包括阿尔茨海默病(AD)、非髓性甲状腺癌(FNMTC)、肥胖、自身免疫性脑脊髓炎(EAE)、胃癌和白血病。在AD中,Smek1的变异与葡萄糖代谢下降相关,可能具有保护作用,可作为AD治疗的新靶点[1]。在FNMTC中,Smek1的错义突变可能导致肿瘤抑制功能的丧失,促进细胞增殖和迁移[2]。在肥胖中,Smek1的缺失可能促进葡萄糖摄取,改善肥胖相关的代谢功能障碍[3]。在EAE中,Smek1的缺失可能加剧实验性自身免疫性脑脊髓炎的病情,通过激活促炎小胶质细胞和抑制IDO1-AhR通路[4]。在胃癌中,Smek1可能通过调节基因表达影响肿瘤微环境和预后[5]。在白血病中,Smek1可能通过调节MAPK3、AKT、JAK/STAT、NFκB和TGFβ信号通路影响白血病细胞的生长和凋亡[8]。
此外,Smek1还参与胚胎干细胞(ESC)的分化过程。在ESC中,Wnt信号通路参与细胞命运决定,而Smek1通过促进组蛋白脱乙酰化来抑制Wnt靶基因brachyury的转录,从而维持ESC的多能性[6]。在皮质神经发生过程中,Smek1与Ryk-ICD结合,调节其核定位和功能,共同介导神经细胞命运的决定[7]。
综上所述,Ppp4r3a(Smek1)是一种重要的PP4调节亚基,参与细胞周期的调控、信号转导、DNA损伤修复和细胞凋亡等多种生物学过程。Smek1在多种疾病中发挥重要作用,包括阿尔茨海默病、非髓性甲状腺癌、肥胖、自身免疫性脑脊髓炎、胃癌和白血病。此外,Smek1还参与胚胎干细胞的多能性维持和皮质神经发生过程。Smek1的研究有助于深入理解PP4信号通路的功能和疾病发生机制,为疾病的治疗和预防提供新的思路和策略。
参考文献:
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